Back in 1970, the word on Rep. Adam Clayton Powell Jr. was that, after a quarter-century in the House, it was time for him to go.

At 61 years of age and enmeshed in ethics controversies, Powell was long known for his flamboyance. He was also known for his chronic absenteeism, and a young state assemblyman by the name of Charles Rangel promised if elected he would be a full-time congressman.

Rangel went on to defeat Powell in a five-candidate Democratic primary by just over 200 votes (32.6-31.8 percent).

Flash forward 42 years. Now it's Rangel, 82 and saddled with health and ethics problems, who is in the toughest battle of his long career, facing four challengers in Tuesday's primary. If Powell was the quintessential outsider, delighting in thumbing his nose at those in political power, Rangel had been a popular, proud member of the establishment for ages and had a history of working with members of both parties to arrive at solutions.

That sentiment quickly came to an end, however, in 2010, when the ethics committee charged him with 13 counts of violating House rules, including failing to report rental income from a villa in the Dominican Republic and using a rent-controlled Harlem apartment for a campaign office. In quick succession, he was forced to relinquish his chairmanship of the Ways and Means Committee in March, held to 51 percent of the vote in a six-way Democratic primary in September, the obligatory re-election in November (yes, with a landslide 80 percent, but his lowest general election tally ever) and a censure by the full House in December.

To make matters worse, his district, the new 13th, once centered in Harlem and overwhelmingly African-American, has been extended to Hispanic areas of the Bronx and is now majority Latino. That's good news for his main challenger, Bronx state Sen. Adriano Espaillat, who is campaigning on the "time for a change" theme and would be, if elected, the first Dominican-American member of Congress in history.

Two years ago, before the House took its censure vote, President Obama described Rangel as "somebody who's at the end of his career," adding, "I'm sure that what he wants is to be able to end his career with dignity."

Charlie Rangel could have walked away after his re-election in 2010 but he didn't. He may still survive Tuesday's primary, as Espaillat is competing with three other challengers, including former Bill Clinton adviser Clyde Williams, for the anti-Rangel vote. Former New York City Mayor Ed Koch was quoted in the New York Times last week as saying, "I want him to leave on his own and not be pushed out." But sometimes we don't all get to make that choice.

Other New York primaries to watch. In the new 7th CD, Rep. Nydia Velazquez (D), who is openly feuding with Brooklyn Democratic Party leader Vito Lopez, is being challenged by city Councilmember Erik Martin Dilan. In the new 8th, also in Brooklyn, where Rep. Ed Towns (D) is retiring, mainstream Democrats are going all out for state Assemblyman Hakeem Jeffries; his opponent, Councilmember Charles Barron, has been accused of a history of making anti-Semitic and racist statements. Obama has made the unusual move of getting involved in this contest, endorsing Jeffries.

In addition: Rep. Gary Ackerman (D-Queens) is retiring in the new 6th CD ... the seats of Reps. Bob Turner (R-old 9th) and Maurice Hinchey (D-old 22nd) have been eliminated; Hinchey is retiring and Turner is seeking the GOP nomination to face Sen. Kirsten Gillibrand (D).

Utah Senate. Orrin Hatch, first elected to the Senate back in 1976, is facing a tough primary challenge on Tuesday from Dan Liljenquist, a 37-year-old Tea Party favorite and former state senator who says Hatch, at 78, is no longer the energetic conservative he was decades ago.

But Hatch seems to have learned a lesson after having watched the defeats of his former Utah colleague Bob Bennett in 2010, as well as fellow Republican Sen. Dick Lugar of Indiana earlier this year. Both Bennett and Lugar lost to conservative opponents who suggested they had outstayed their welcome and had long ago lost their conservative credentials. Unlike Lugar, who thumbed his nose at Tea Party opponents until it was too late, Hatch actively courted the right, voted more regularly with conservatives, toughened his anti-Obama rhetoric, and raised some $10 million to fend off Liljenquist's attacks. It may pay off; Hatch is favored to win renomination.

Political Updates. I post periodic political updates during the week on Twitter. You can follow me at @kenrudin. Time for one question from the mailbox.

Q: How often in American history have national convention delegates refused to support their party's nominee? — Duane Joostberns, Hamilton, Mich.

A: If you're asking whether delegates elected during the primaries have ever decided to vote for another candidate at the convention — an act that essentially nullified voters' preferences made in the primaries — the answer is no. At least, not since presidential primaries in 1972 became the path to winning the nomination. (Hubert Humphrey won the Democratic nomination in 1968 without having entered, let alone won, a single primary.) In 1980, after the Democratic primaries had ended, supporters of Sen. Edward Kennedy attempted to overturn a proposed rules change by the forces committed to President Jimmy Carter, Kennedy's rival, that would bind all delegates to vote for the candidate on the first ballot they were pledged to during the primaries. Kennedy's challenge was defeated the first day of the convention, which essentially ended his candidacy.

In Memoriam. Former Rep. Norman Lent, a moderate conservative Republican from Long Island, N.Y., who defeated a liberal Democratic incumbent, Allard Lowenstein, in 1970 and served 22 years in the House, died June 11. He was 81. Lent played a leading role in fighting for environmental protection and had a reputation for working across the aisle with Democrats ... Norbert Tiemann, whose one term as governor of Nebraska (1967-70) was best remembered for his shepherding in a state sales-income tax, a move that hurt him with conservatives in his own party and contributed to his defeat in 1970 to Democrat James Exon. Tiemann, 87, died on June 19 ... Edward Costikyan, 87, a former adviser to New York governors and mayors who successfully took on Tammany Hall and Carmine DeSapio in the early 1960s but who unsuccessfully tried to become mayor of New York City in 1977. He died on June 22.

Political Junkie segment on Talk of the Nation. Each Wednesday at 2 p.m. ET, the Political Junkie segment appears on Talk of the Nation (NPR's call-in program), hosted by Neal Conan with me adding color commentary, where you can, sometimes, hear interesting conversation, useless trivia questions and sparkling jokes. Last week's show discussed whether or not Marco Rubio was really and truly on Mitt Romney's VP short list, a look ahead to the upcoming primaries in New York and Utah, and a focus on the Latino vote with Democratic strategist Ruy Teixeira of the Center for American Progress, and Republican strategist Mario Lopez of the Hispanic Leadership Fund.

Podcast. There's also a new episode of our weekly podcast, "It's All Politics," up every Thursday. It's hosted by my partner in crime, Ron Elving, and me.

And Don't Forget ScuttleButton. ScuttleButton, America's favorite waste-of-time button puzzle, can usually be found in this spot every Monday or Tuesday. A randomly selected winner will be announced every Wednesday during the Political Junkie segment on NPR's Talk of the Nation. You still have time to submit your answer to last week's contest, which you can see here. Not only is there incredible joy in deciphering the answer, but the winner gets a TOTN T-shirt!

Mailing list. To receive a weekly email alert about the new column and ScuttleButton puzzle, contact me at politicaljunkie@npr.org.

******* Don't Forget: If you are sending in a question to be used in this column, please include your city and state. *********

This day in political history: The Supreme Court, in a 6-1 ruling, says prayer in public schools is unconstitutional. In the majority opinion, Justice Hugo Black said the recitation of prayers violated the First Amendment to the Constitution, which forbids government establishment of a religion. President Kennedy suggested that the "easy remedy" was to "pray a good deal more at home and attend our churches with a good deal more fidelity." Conservatives in Congress, led by Senate Judiciary Committee chair James Eastland, D-Miss., offered constitutional amendments to overrule the Court (June 25, 1962).